I'm very sorry for the delayed response. I was recovering from Turkey-toxicity here in the states
For cases where Javascript is loading our tags, as you've seen, they usually won't render properly. Our System plugin is what replaces {JFBCLogin} with the proper HTML and that isn't always triggered when loaded via Javascript.
However, it's *usually* pretty simple to add the proper HTML to the page to make the social login buttons work. If you're already able to add the modal output, this should be straightforward. Instead of {JFBCLogin}, use the following code for each social network:
<a class="sc_fblogin" href="javascript:void(0)" onclick="jfbc.login.provider('facebook');">
<img src="/media/sourcecoast/images/provider/facebook/icon_label.png" alt="Login With Facebook" title="Login With Facebook"></a>
That is the same code the login tag would enter. The main important bit is:
<a href="javascript:void(0)" onclick="jfbc.login.provider('facebook');">...</a>
You can put whatever you want in the ... (an image, simple text, etc). The <a> tag with the onclick Javascript is what will load the proper network. You can replace 'facebook' with 'google', 'twitter', 'linkedin', etc for each network.
I hope that helps, but if you need anything else with this, just let us know!
Thanks,
Alex